How to use this calculator
- Select the values that you know.
- Enter the values and select each unit.
- For a mass input, enter a formula or a known molar mass.
- Calculate and review the normalized moles and solution volume.
Formula and variables
M = n / V
| Symbol | Meaning | Unit |
|---|---|---|
| M | amount concentration | mol/L |
| n | amount of solute | mol |
| V | solution volume | L |
Worked example
Dissolving 0.5 mol in a final volume of 2.0 L gives M = 0.5 / 2.0 = 0.25 mol/L.
Interpretation
Molarity is amount of solute per liter of final solution. Unit normalization occurs before division.
Common mistakes
- Use final solution volume, not solvent volume alone.
- Do not enter zero or negative volume.
- In mass mode, verify the explicit molecular formula.
Frequently asked questions
Does molarity use solution volume or solvent volume?
Molarity uses the final total solution volume.
Can I calculate molarity from a solute mass?
Yes. Use a chemical formula or a known molar mass to convert the solute mass to moles.
Can the calculator solve for moles or volume?
Yes. Select the required solve mode and enter the two known values.
Can I use scientific notation?
Yes. Enter values such as 6.022e23 or 1.0e-6 in a numeric field.
How should I round the result?
Keep extra digits during the calculation. Round the final result to the precision required by your data.